Mechanism for intermittently advancing and stopping material



May 12,1970 LA GRANG ED. WHITMORE EI'AL 3,511,426 MECHANISM FORINTERMITTENTLY ADVANCING AND STOPPING MATERIAL Filed Aug. '7, 1968 4Sheets-Sheet 1 if 70/4/12 K5 y 1970' LA GRANGE o. WHITMORE E A 3,511,426

MECHANISM FOR INTERMITTENTLY ADVANCING AND STOPPING'MATERIAL Filed Aug.'7, 1968 I 4 Sheets-Sheet 2 Z a 6. 419 G-ZZDM/f/Vi F0 :15 SflfF/WHA/ y1970 LA GRANGE D.'WHITMORE 'ETAL 3,511,426

r MECHANISM FOR .INTERMITTENTLY ADVANCING AND STOPPING-MATERIAL v FiledAug. '7, 1968 v j 4 Sheets-Sheet 3 I F? HE By l :40;

y-1 0 LA GRANGE D. WHITMORE ETI'AL 3,511,426

. MECHANISM FOR INTERMITTENTLY ADVANCING AND STOPPING MATERIAL FiledAug. V, 1968 4 Sheets-Sheet 4.

| l 04w Poi/El pen 5 Ill/7'5 570/ M6775 I s/mFr vfmc/rr United StatesPatent O U.S. Cl. 226145 7 Claims ABSTRACT OF THE DISCLOSURE An improvedmechanism is provided for advancing continuous length paper, and otherlengths of materials, in accordance with a precise stepwise advancement.The mechanism includes a pair of wheels between which the material isadvanced, and one wheel functions as a drive wheel for intermittentlyadvancing the material. The drive wheel is rotated by a drive shaftwhich is oscillated back and forth about its axis of rotation, and astopping mechanism precisely stops the drive shaft in a position whichadvances paper between the pair of Wheels. The drive shaft may be drivenby an electromagnetic solenoid coil which periodically draws a rotormember carried by the drive shaft into an air space formed within thecoil. When the rotor is drawn into the coil, the drive shaft functionsto turn the drive wheel in a direction which advances paper, and areturn spring turns the drive shaft in an opposite direction when thesolenoid coil is de-energized. The stopping mechanism for preciselystopping forward advancement of material may comprise a ratchet meanscarried by the drive wheel. A cam plate is mounted adjacent to theratchet means, and a pawl is lifted ard lowered by the cam platerelative to the ratchet means to periodically engage a tooth of theratchet for precisely stopping the forward rotation of the drive shaft.

BACKGROUND AND BRIEF DESCRIPTION OF INVENTION This invention relates tomechanisms for advancing paper and other material, and in particular,the invention is concerned with an improved mechanism for advancingcontinuous length paper and for intermittently stopping the advancementfor a precise period of time so that a collateral operation, such asprinting, can be carried out. The improved mechanism of the presentinvention permits very high speed advancements of a material.

It is known in the prior art to provide for various mechanisms and meansfor advancing paper and other materials. Also, it is known to advancepaper on an intermittent program whereby the paper is periodicallystopped before a subsequent advancement. Representative of the prior arton this subject are the mechanism shown in the U.S. Pats. 948,944;1,827,652; 2,077,925; 2,311,903; 2,530,961; 2,541,013; 2,912,100;3,125,309; and 3,292,832. As can be appreciated from the disclosures ofthe just mentioned patents, many of the prior art devices on thissubject have consisted of relatively complex apparatus requiring a largenumber of precisely manufactured and carefully related elements. Incontrast the present invention offers a relatively simple mechanism forintermittently advancing and stopping the movement of a material in asingle direction and with such precision that a printing operation, orother collateral functions, can be performed on the same material.Although the invention will be deinvention be applied in any situationwhere it is desired to intermittently advance and stop a material. Thematerial may be in the form of a sheet, card, film, or other datareceiving or recording form, and collateral functions such as printing,punching, or recording, may be carried out in connection with theintermittent advancement of the material.

In its basic form, the mechanism of this invention includes a pair ofwheels, or equivalent devices, which function to receive and advance amaterial between them. One wheel functions as a friction wheel forpreventing backward movements of the material, and the second wheelfunctions as a drive Wheel for applying periodic forward movements tothe material. Thus, periodic advancements of the material between thetwo wheels is accomplished in a single forward direction. The drivewheel is periodically advanced about its axis of rotation by a driveshaft means connected to the wheel. A one-Way clutch between the drivewheel and the drive shaft means is such that the drive wheel is engagedby the drive shaft only during rotations of the drive shaft which willadvance material in the desired direction between the drive wheel andthe friction wheel. Opposite rotations of the drive shaft are notimparted to the drive wheel, thereby preventing a backing up of thematerial. A driving means is operatively associated with the drive shaftto oscillate the drive shaft back and forth about its axis of rotation.In one form of the invention the driving means may include a solenoidwhich is periodically energized with electric current to draw a rotorinto the solenoid. The rotor is rigidly fixed to the drive shaft suchthat the drive wheel is rotated for an advancing movement of paper whenthe rotor is drawn into the solenoid. When the solenoid is de-energized,a return spring draws the rotor and the drive shaft back to a startingposition for a subsequent rotation in a forward direction.

A stopping mechanism is associated with the drive wheel means forpositively and precisely stopping the advancement of material by thedrive wheel. Although the material can be stopped by merelyde-energizing the solenoid, it is important to be able to advancematerial for a precise distance and to stop the material for a preciseperiod of time so that collateral operations, such as printing, can becarried out on the same material. Thus, the stopping means functions toprecisely stop an advancing movement of the material near the end of itsintermittent advancement. The stopping means may comprise a ratchetwhich is fixed to the drive wheel, and an associated cam plate may becarried by the drive shaft for dictating movements of a pawl relative tothe ratchet. The pawl may be associated with the ratchet so as to benormally biased into engagement with teeth formed in the ratchet, andthe cam means is of a configuration to periodically lift the pawl out ofengagement with the ratchet. In one form of the invention, the cam plateis fixed to release the pawl near the end of a rotation of the driveshaft in the direction which advances material. Also, the cam means isof a configuration to periodically lift the pawl out of engagement withthe ratchet during opposite motions of the drive shaft. The drive wheeland friction wheel may be mounted on separate shafts which are parallelto each other, and each wheel may be provided with one-way clutchingdevices which permit rotational movements only in directions whichaccommodate the advancement of a material between the two wheels.

With the mechanism of the present invention, there is provided arelatively simple apparatus which is easily manufactured and maintained,and the apparatus is very precise in dictating advancing and stoppingmovements to paper, film, or any other material which must beintermittently advanced. Additional details and advantages of thepresent invention will become apparent in the more detailed discussionwhich follows. In the detailed discussion reference will be made toaccompanying drawings as further identified below.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of oneembodiment of the basic mechanism of the present invention as seen atthe beginning of an oscillation which will advance material between thedrive wheel and a friction wheel;

FIG. 2 is a perspective view similar to that of FIG. 1 but showingrelationships of elements in the mechanism when an advancing motion hasbeen carried out and stopped;

FIG. 3 is an end elevational view of a slightly different arrangement ofthe basic mechanism shown in FIG. 1;

FIG. 4 is a side elevational view of the mechanism shown in FIG. 3;

FIG. 5 is a top plan view of the FIG. 3 mechanism, with certain portionsomitted from the drawing for clarity; and

FIG. 6 is a graphic example of a typical operation of the mechanism whenused in connection with a printing operation.

DETAILED DESCRIPTION OF THE INVENTION As discussed above, the presentinvention provides for an improved mechanism which may be used forprecisely advancing and stopping paper, or other material, forincrements of advancement in a single direction.

Referring to FIGS. 1 and 2, basic elements of the mechanism of thepresent invention are illustrated. The illustrated mechanism includes apair of wheel means which includes a drive wheel means 10 and a frictionwheel means 12. The pair of wheels are positioned relative to oneanother to frictionally contact opposite surfaces of a flat form ofmaterial 14 which is to be intermittently advanced between the pair ofwheels. The material 14 may be in the form of a paper strip, card, film,ribbon, drive belts, or in any other form for being periodicallyadvanced in conjunction with a pair of wheels 10 and 12. The pair ofwheels may be mounted on shafts, which are substantially parallel to oneanother, as illustrated, and a shaft 16 which is associated with thedrive wheel means 10 may be considered a drive shaft means. The drivewheel means 10 functions to frictionally engage one surface of thematerial 14 so as to advance the material in the direction of the arrowwhen the drive wheel means 10 is rotated in an advancing direction(clockwise as viewed in FIGS. 1 and 2) about the central longitudinalaxis of the drive shaft means 16. The friction wheel means 12 functionsto support the material 14 on an opposite surface while it is beingadvanced and to prevent a backward movement of the material after it hasbeen advanced for a predetermined distance. Each of the wheels 10 and 12may be mounted on their respective shafts with one-way clutch bearingsof known construction (see for example the type of clutching mechanismillustrated in US. Pat. 1,513,021). The friction wheel means 12 isprovided with one-way clutch bearings which permit free rotationalmovements only in a counterclockwise direction, as viewed in FIGS. 1 and2, and the drive wheel means is provided with a one-way clutch bearingmeans which permits driving movements of the wheel 10 only in aclockwise direction of movement, as illustrated. Thus, the pair ofwheels 10 and 12 are provided with clutching mechanisms, or theirequivalents, which permit rotational movements of the two wheels only indirections which accommodate the desired advancement of the material 14in a single direction between the pair of wheels.

The drive wheel means 10 is rotated for a limited distance about itsaxis of rotation by a driving means which is operatively associated withthe drive shaft means 16.

As explained above, the drive wheel means 10 is mounted on the driveshaft 16 so as to be driven only in a direction which accommodatesadvancement of material. To accomplish intermittent advancing rotationsof the drive wheel means 10, the drive shaft means 16 is oscillated backand forth about its axis of rotation (the central longitudinal axis ofthe drive shaft). Rotation result in an engagement of the drive shaftmeans (through the one-way clutch mechanism) with the drive wheel means10 so as to rotate the drive wheel means 10. Such rotations result in anadvancing of the material 14 between the wheels 10 and 12 because of thefrictional engagement of the drive wheel means 10 with an upper surfaceof the material 14. However, rotations of the drive shaft means 16 in anopposite direction (i.e., a counterclockwise direction as viewed inFIGS. 1 and 2) result in no substantial turning movement of the wheelmeans 10 in a counterclockwise direction because the one-way clutchmounting of the drive wheel 10 permits free movement of the drive shaftrelative to the drive wheel when the drive shaft is rotated in acounter-clockwise direction. Thus, the drive shaft means 16 is rockedback and forth about its axis of rotation for periodically rotating thedrive wheel means 10 in a direction which advances paper between thedrive wheel and the frictional wheel means 12. A preferred form ofdriving means for oscillating the drive shaft 16 back and forth isillustrated by solenoid coil means 18 and rotor means 20 of FIGS. 1 and2. The solenoid coil may be of any well known construction, and itincludes circuiting means for automatically energizing and de-energizingthe coil by a flow of electrical current through the coil. Since thesolenoid itself is not a separate part of the present invention, acircuiting diagram and associated electrical components have beenomitted from the drawings. When the solenoid coil 18 is energized by aflow of current, a magnetic field is established in an air gap formed inthe solenoid core. During such energization of the coil, the rotor 20 isdrawn downwardly into the air gap from the position shown in FIG. 1 tothe position shown in FIG. 2. The rotor means 20 is fixed in its mountedrelationship to the drive shaft means 16, and therefore, downwardmovements of the rotor result in a clockwise rotation of the drive shaft16. As described above, a clockwise rotation of the drive shaft appliesa similar clockwise rotation to the drive wheel means 10 for effectingan advancement of paper between the drive wheel 10 and a friction wheel12. Thus, there is provided in the coil 18 and rotor 20 combination adriving means for periodically rotating the drive shaft 16 in adirection which causes an advancement of paper by the drive wheel means10. When the coil 18 is de-energized, the rotor 20 is returned to itsFIG. 1 position by a return spring means 22 which is biased to normallyrotate the drive shaft means 1'6 and rotor 20 in a counterclockwisedirection to the position shown in FIG. 1.

It can be appreciated that the elements described so far provide for aperiodic, stepwise advancement of paper, or other material in a singledirection. However, such an advancement is difficult to control at veryhigh speeds, and precise control becomes important when collateraloperations, such as printing, cutting or punching are to be carried outat precise locations on the material or at precise times as related tomovement of the material. Accordingly, a stopping mechanism isincorporated in the apparatus of the present invention to provide for aprecise, periodic stopping of the material 14 near the end of eachadvancement movement.

The stopping mechanism which is associated with the apparatus of thisinvention comprises means for rapidly and precisely stopping and brakingadvancing (clockwise in FIGS. 1 and 2) movements of the drive Wheelmeans 10 near the end of each advancing rotation of the drive shaftmeans 16. Although the stopping means may be provided in several forms,one embodiment of a very practical stopping mechanism is illustrated inFIGS.

1 and 2. The stopping mechanism which is illustrated includes a ratchetmeans 24 and a cam plate means 26. The cam plate means 26 is fixed tothe drive shaft means 16, and thus, the cam plate means 26 oscillatesback and forth with all rotational movements of the drive shaft meansabout its central longitudinal axis. The ratchet means is fixed to thedrive wheel so that direct control of the drive wheel may beaccomplished, and the ratchet means is mounted relative to the driveshaft 16 to be free of non-advancing rotation of the drive shaft means.A single pawl element 28 is provided for cooperation with the ratchetmeans 24 and the cam plate means 26 to control advancing and stoppingmovements of the drive wheel means 10. The pawl 28 is positioned to havea normal bias in the direction of the ratchet means 24, and the camplate means 26 functions to lift the pawl 28 out of engagement with theratchet means 24. As seen in FIG. 1, the cam plate means 26 is of such aconfiguration that the pawl member 28 is normally lifted out ofengagement with the ratchet means 24 during initial advancing movementsof the drive shaft means 16 and during all return rotations of the driveshaft means from the position shown in FIG. 2 to the position shown inFIG. 1. However, when the solenoid coil 18 is actuated to draw the rotor20 downwardly, to the position shown in FIG. 2, a cam surface 30 on thecam plate means 26 allows the pawl member 28 to fall into engagementwith a ratchet tooth 32 of the ratchet means 24.

Considering a typical operation of the mechanism illustrated in FIGS. 1and 2, an energization of the coil 18 will result in a downward movementof the rotor 20. Such. movement results in a rotational oscillation ofthe drive shaft means 16 in a direction which drives the drive wheelmeans (and its associated ratchet means 24) clockwise for advancing thematerial 14 between the drive wheel means 10 and the friction wheelmeans 12. As the rotor 20 moves downwardly to the position shown in FIG.2, the cam plate means 26 is carried through an arc of rotation whichcorresponds to the clockwise rotation of the drive shaft means 16. Nearthe end of the rotation of the drive shaft means 16, the coil 18 isde-energized and the pawl 28 falls downwardly into engagement with atooth 32 of the turning ratchet means 24. This engagement causes a rapidstopping of the ratchet means 24 and of the drive wheel means 10. Inthis manner, the distance of rotational movement of the drive wheel 10and its associated drive shaft 16 is precisely controlled and limited bythe configuration of the cam surface 30 and the time at which the pawl28 engages the ratchet tooth 32. Thus, the distance of advancement ofmaterial 14 is carefully controlled and limited. A sprague spring 34 maybe provided for contacting a surface of the drive wheel means 10 toprevent a backlash of the drive wheel means 10 immediately after impactof the pawl 28 with the ratchet tooth 32. Also, the friction wheel means12 assists in preventing any momentary backup of the paper 14 since aone-way clutch prevents the frictional wheel means 12 from rotating in aclockwise direction. The shaft upon which the friction wheel 12 ismounted is a fixed shaft and does not rotate in the embodimentillustrated in FIGS. 1 and 2. When the advancing paper has been stoppedby the mechanism, and is in the position shown in FIG 2, de-energizationof the solenoid coil 18 permits a reverse rotation of the drive shaftmeans 16 in a counterclockwise rotation. The reverse rotation of thedrive shaft means 16 permits a resetting of the mechanism for asubsequent advancing movement. As shown in FIG. 1, a stop limit means 36may be provided to limit the return motion of the drive shaft means 16under the influence of torsion spring 22. The limit means 36 may includean adjustable screw which is threaded within a fixed cane be carefullyset and adjusted.

It should be understood that the mechanism illustrated in FIGS. 1 and 2is intended to disclose the basic elements and relationships of thepresent invention. Of course, all elements are assembled and mounted ina suitable housing, or in connection with other structures which fix therelationships defined above. FIGS. 4 through 5 illustrate the m chanismof the present invention in a form in which it may be utilized in anactual operation for intermittently advancing material. Therelationships of the various elements have been re-arranged somewhatfrom what is shown in the perspective views of FIGS. 1 and 2, but it canbe appreciated that the drive wheel means 10 and its associated drivingand stopping means may be arranged in any suitable attitude in ccordancewith the principles of the present invention. FIG. 5 is incomplete tothe extent that the ratchet means 24, the cam plate means 26, and thepair of wheels 10 and 12 have been omitted from the drawings so that thepawl 28 and the spring 34 are fully illustrated.

FIG. 6 illustrates a typical working cycle for the mechanism of thepresent invention when utilized in combination with printing apparatus.It is contemplated that the invention may be used in a variety ofsituations where it is desired to precisely advance and stop a runninglength of material, and one such situation involves a use of themechanism in combination with a printing device. With the improvedcharacteristics of the device of this invention, it is possible toadvance paper in a stepwise manner for receiving printed informationfrom a printing mechanism. As an example of operation, it is possible toprint at the high rate of 1800 or 2400 lines per minute with 12 or 15characters respectively being applied to each line during the stoppedintervals of the periodically advancing paper. Where such high speedprinting is involved, it is necessary that the increments of movement ofthe paper be precise in distance and in timing relative to the printingoperation which is taking place concurrently with the advancement of thepaper. FIG. 6 is a timing diagram of a system which advances paper forprinting at the rate of approximately 40 lines per second, and all timesreferred to on the graph are in milli-seconds. It can be seen that thecoil 18 is de-energized just prior to the time that the pawl 28 engagesand stops the ratchet 24 during each cycle. Other examples of operationinclude the application of information and color codes to tickets, andpunching or cutting operations may be combined with such printingtreatments of the advancing paper.

Having described the structural features of the mechanism of thisinvention, it can be seen that a relatively simple mechanism has beenprovided for effecting a very rapid, but carefully controlled,intermittent advancement of a length of material. The mechanism may bemanufactured from known materials which provide the desired functionsand wearing characteristics, and equivalent structures may besubstituted for the illustrated embodiments of the invention. The pairof Wheels 10' and 12 are provided with surfaces which make a frictionalcontact with whatever material is being advanced, and equivalentstructures may be substituted for the drive and friction wheels whichhave been illustrated. All equivalent and obvious variations of thedisclosed mechanism are intended to be included within the scope of thisinvention as claimed below.

What is claimed is:

1. A mechanism for automatically and intermittently advancing lengths ofmaterial for predetermined distances in a single direction of movement,comprising:

a drive wheel means and a friction wheel means positioned relative toone another to receive between them the material which is to beadvanced, said friction wheel means being mounted on a shaft so as torotate only in a direction which will accommodate said single directionof movement for said material,

a drive shaft means connected to said drive wheel means for rotatingsaid drive wheel means only in a direction which advances said materialin said single direction when the material is positioned between thedrive wheel means and the friction wheel means,

driving means operatively associated with said drive shaft means tooscillate the drive shaft means back and forth about its axis ofrotation,

a ratchet means fixed to said drive wheel means for movement therewith,

a pawl means positioned and biased to contact said ratchet means toperiodically stop rotational movement of said drive wheel means in thedirection which drives said drive Wheel means and which advances thematerial,

a cam means fixed to said drive shaft means for lifting said pawl meansout of engagement with the ratchet means, said cam means being of aconfiguration (a) to periodically release said pawl means for a stoppingengagement with said ratchet means during a rotation of the drive shaftin one direction of rotation, and (b) to periodically lift said pawlmeans out of engagement with said ratchet means during a rotation of thedrive shaft means in an opposite direction of rotation, whereby saidmaterial is advanced between the drive wheel means and the frictionwheel means during oscillations of said drive shaft means in said onedirection of movement and wherein said advancement is stopped at apredetermined point when said pawl means engages and stops the ratchetmeans.

2. The mechanism of claim 1 wherein driving means includes anelectromagnetic means comprising a rotor and a solenoid coil combinationof the type in which the solenoid coil can be periodically magnetized todraw the rotor into an air space formed in said solenoid coil, saidrotor member being fixed to said drive shaft means.

3. The mechanism of claim 2 wherein said drive shaft means is turned insaid one direction of rotation by an energization of said solenoid coil,and including a return spring means for rotating said drive shaft meansin an opposite direction of movement whenever said solenoid coil isde-energized.

4. The mechanism of claim 1 wherein said drive wheel means is connectedto said drive shaft means with a oneway clutch means which permitsdriving movements to be applied to said drive wheel means only when saiddrive shaft means is rotated in said one direction of rotation.

5. The mechanism of claim 1 wherein said friction wheel means is mountedon a fixed shaft having a longitudinal axis substantially parallel tothe longitudinal axis of the drive shaft means, and including a one-wayclutch means for connecting said friction wheel to said fixed shaft sothat said friction wheel can rotate only in a direction whichaccommodates the advancement of material between the drive wheel meansand the friction wheel means 6. The mechanism of claim 1, and includinga braking member which contacts said drive wheel means to preventbacklashing of the drive wheel means when it is stopped.

7. A mechanism for automatically and intermittently advancing lengths ofmaterial for predetermined distances in a single direction of movement,comprising:

a drive wheel means and a friction wheel means positioned relative toone another to receive between them the material which is to beadvanced, said friction wheel means being mounted on a shaft so as torotate only in a direction which will accommondate said single directionof movement for said material,

a drive shaft means connected to said drive wheel means for rotatingsaid drive wheel means only in a direction which advances said materialin said single direction when the material is positioned between thedrive wheel means and the friction wheel means,

driving means operatively associated with said drive shaft means torotate the drive shaft means back and forth about its axis of rotation,

stopping means for stopping oscillations of said drive Wheel means insaid single direction which advances material between the drive wheelmeans and the friction wheel means, said stopping means including a cammeans for actuating said stopping means, whereby material isautomatically advanced and stopped for a period of time before asubsequent advancing movement is begun.

References Cited UNITED STATES PATENTS 3/1957 Forkner 226145 X 3/1959Panissidi 226156 RICHARD A. SCHACHER, Primary Examiner UNITED STATESPATENT OFFICE CERTIFICATE OF CORRECTION Patent No 3 5 11 4 26 Dated 1 21970 lnventofls) LaGrange D. Whitmore and Roy E. Sherman It is certifiedthat error appears in the above-identified patent and that said LettersPatent are hereby corrected as shown below:

At the heading of each drawing and immediately following the title incolumn 1 the principal inventor's first name is incorrectly broken upinto two words. In each instance the name "La Grange" should readLaGrange Column 1, line 56, "mechanism" should read mechanisms Column 4,line 7, "Rotation" should read Rotations of the drive shaft means 16 ina clockwise direction Attest:

Ed Emma h mm x. sauuw. Ja- Auestmg 0mm comissioner or Pam" FORM PO-IO5O(IO-69] USCOMM DC 60376-959 w u s covenant!" nmnmc ornc: nus 0-166-334

